QR Codes

Dux Shell

QR Codes

The dms qr command generates QR codes from text, stdin, or saved WiFi networks. Codes render directly in the terminal, export as PNG files, or copy straight to the clipboard — making it useful both interactively and from scripts or plugins.

Quick Start

# Render in the terminal
dms qr "https://example.com"

# Save a PNG
dms qr "https://example.com" -o code.png

# Pipe PNG bytes anywhere
dms qr "https://example.com" > code.png

# Share your WiFi
dms qr wifi MyNetwork

Input Sources

Source	Command
Argument	dms qr "some text"
Stdin (piped)	echo -n "data" | dms qr
Stdin (explicit)	dms qr -
Saved WiFi network	dms qr wifi <ssid>

Output Destinations

Output is automatic by default: a terminal render when stdout is a TTY, raw PNG bytes when piped. Destinations can be combined freely.

Flag	Description
--output / -o	Save a PNG to a file
--stdout	Write PNG bytes to stdout
--clipboard	Copy the PNG image to the clipboard
--copy-text	Copy the source text to the clipboard
--render	Force terminal rendering
--no-render	Never render to the terminal

When PNG bytes go to stdout and --render is also set, the terminal render goes to stderr so the streams stay separate:

dms qr "text" --stdout --render > code.png   # PNG in file, preview on screen

Encoding Options

Flag	Description
--ecc	Error correction level: L, M, Q, H (default M, or H with --logo)
--qr-version	Force QR symbol version 1-40 (default: auto)

Higher error correction makes the code denser but more damage-resistant. H survives ~30% obstruction, which is why it becomes the default when a logo is overlaid.

Styling Options

PNG

Flag	Description
--module-size	Pixels per module, 1-255 (default: auto)
--fg	Dark module color (#RGB or #RRGGBB)
--bg	Light module color (#RGB or #RRGGBB)
--transparent	Transparent background (overrides --bg)
--border	Border width in pixels (default: auto)
--shape	Module shape: square (default) or circle
--logo	Center a PNG/JPEG logo on the code
--logo-scale	Max logo size as 1/N of the code (default: 5)

# Themed, rounded modules with a logo
dms qr "https://danklinux.com" \
  --shape circle \
  --fg '#1a1b26' --bg '#c0caf5' \
  --logo ~/Pictures/logo.png \
  -o branded.png

tip

A logo larger than 1/N of the final image is skipped by the renderer. If your logo doesn't appear, raise --module-size or --logo-scale.

note

Circle modules are an aesthetic choice — modern phone scanners read them fine, but some older decoders only handle square modules.

Terminal

Flag	Description
--invert	Swap colors (for light terminals)
--quiet-zone	Margin around the code in modules (default: 2)
--fg / --bg	Override the render colors

Terminal rendering paints both polarities explicitly, so codes scan correctly on dark and light terminal themes alike. If a scanner still struggles, try --invert.

WiFi QR Codes

dms qr wifi builds a code that joins a network when scanned.

# Pull the saved password from the running DMS shell
dms qr wifi MyNetwork

# Fully offline with an explicit password
dms qr wifi MyNetwork -p 'hunter2'

# Open network
dms qr wifi CoffeeShop --security nopass

Flag	Short	Description
--password	-p	WiFi password (builds offline, no shell needed)
--security		Security type: WPA (default), WEP, nopass
--hidden		Mark the network as hidden

Without --password, the saved credentials are fetched from the running DMS shell — the same mechanism the network panel uses. Special characters in SSIDs and passwords are escaped automatically.

All output and styling flags work here too:

dms qr wifi MyNetwork --clipboard --no-render
dms qr wifi MyNetwork -o guest-wifi.png --module-size 16

Scripting & Plugins

Since piped output is raw PNG and errors go to stderr with a non-zero exit code, dms qr composes cleanly:

# QR of the current clipboard contents
dms clipboard paste | dms qr

# Show a file's contents as a code in a notification-sized PNG
dms qr - < token.txt --module-size 8 -o /tmp/token.png

# Feed another tool without touching disk
dms qr "otpauth://totp/..." --stdout | imv -

All Options

Flag	Short	Description
--ecc		Error correction: L, M, Q, H (default M, or H with --logo)
--qr-version		Force QR symbol version 1-40 (0 = auto)
--output	-o	Write a PNG to this file
--stdout		Write PNG bytes to stdout
--clipboard		Copy the PNG image to the clipboard
--copy-text		Copy the source text to the clipboard
--render		Force terminal rendering
--no-render		Never render to the terminal
--invert		Swap colors (for light terminals)
--quiet-zone		Terminal margin in modules (default: 2)
--module-size		PNG pixels per module (0 = auto)
--fg		Dark module color (#RGB or #RRGGBB)
--bg		Light module color (#RGB or #RRGGBB)
--transparent		Transparent PNG background
--border		PNG border in pixels (-1 = auto)
--shape		PNG module shape: square, circle
--logo		Center a PNG/JPEG logo on the PNG output
--logo-scale		Max logo size as 1/N of the code (0 = default of 5)
--help	-h	Show help